1. Field of the Invention
The present invention relates to an information transmission system in which image signals read, for example, from an original are transmitted to a distant recording unit for recording.
2. Description of the Prior Art
The function of a copier has been limited to faithful reproduction of an original and image magnification or reduction with predetermined size ratios. Such a copier functions by illustrating an original with a light source such as a fluorescent lamp or a tungsten lamp, guiding the reflected light through mirrors and lenses to a previously charged photosensitive member to form an electrostatic latent image thereon, and then applying developer to said photosensitive member to obtain a visible image. Thus the imaging process is entirely achieved through mechanical control, and it has therefore been difficult to separate the imaging unit from the original scanning unit. Such copier is therefore unable to adequately respond to the ever increasing demands of information processing.
For this reason there is proposed an information transmission system, generally called a network, for transmitting image signals obtained by photoelectric conversion of an original to a distant recording unit and for information transmission among plural word processor and office computers.
However, in case of information transmission among plural stations in such network, it has been difficult to uniformly distribute the communicating right for utilizing the transmission channel among different stations.
Also it is quite difficult to know the contents of plural stations connected to the communication channel, and there may exist two stations with the same station address, or there may occur an error in the communication.
Also the information transmission under execution may be undesirably affected by a station joining the communication system later